反应详情

A mixture of 74.7 parts of 1-acetyl-4-(4-fluorobenzoyl)piperidine, 46.5 parts of 1,2-ethanediol, 3 parts of 4-methylbenzenesulfonic acid and 810 parts of benzene was stirred for 108 hours at reflux temperature using a water separator. After cooling, the reaction mixture was washed successively with 250 parts of water, 22.5 parts of ammonium hydroxide and 250 parts of water. The organic layer was dried, filtered and evaporated. The residue was purified by column chromatography (silica gel; CHCl3 /CH3COCH3 50:50). The eluent of the desired fraction was evaporated, yielding 50 parts (56.8%) of 1-acetyl-4-[2-(4-fluorophenyl)-1,3-dioxolan-2-yl]piperidine (interm 45).

1. temperatureat reflux temperature
2. temperatureAfter cooling
3. washthe reaction mixture was washed successively with 250 parts of water, 22.5 parts of ammonium hydroxide and 250 parts of water
4. customThe organic layer was dried
5. filtrationfiltered
6. customevaporated
7. customThe residue was purified by column chromatography (silica gel; CHCl3 /CH3COCH3 50:50)
8. customThe eluent of the desired fraction was evaporated